Sewing machine



FIG. 1 is a top view of a sewing machine showing our new design;

FIG. 2 is a front view thereof;

FIG. 3 is a bottom view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a back view thereof; and,

FIG. 7 is a perspective view of a sewing machine showing our new design.

The ornamental design for a sewing machine, as shown and described.